MacDonald shook his obstinate Scotch head. “I’m not convinced yet that there was ever anyone in the house,” said he. “I’m asking you to conseedar” (his accent became more Aberdonian as he lost himself in his argument) “I’m asking you to conseedar what it involves if you suppose that this gun was ever brought into the house, and that all these strange things were done by a person from outside. Oh, man, it’s just inconceivable! It’s clean against common sense! I put it to you, Mr. Holmes, judging it by what we have heard.”

“Well, state your case, Mr. Mac,” said Holmes in his most judicial style.

“The man is not a burglar, supposing that he ever existed. The ring business and the card point to premeditated murder for some private reason. Very good. Here is a man who slips into a house with the deliberate intention of committing murder. He knows, if he knows anything, that he will have a deeficulty in making his escape, as the house is surrounded with water. What weapon would he choose? You would say the most silent in the world. Then he could hope when the deed was done to slip quickly from the window, to wade the moat, and to get away at his leisure. That’s understandable. But is it understandable that he should go out of his way to bring with him the most noisy weapon he could select, knowing well that it will fetch every human being in the house to the spot as quick as they can run, and that it is all odds that he will be seen before he can get across the moat? Is that credible, Mr. Holmes?”

“Well, you put the case strongly,” my friend replied thoughtfully. “It certainly needs a good deal of justification. May I ask, Mr. White Mason, whether you examined the farther side of the moat at once to see if there were any signs of the man having climbed out from the water?”

“There were no signs, Mr. Holmes. But it is a stone ledge, and one could hardly expect them.”

“No tracks or marks?”

“None.”

“Ha! Would there be any objection, Mr. White Mason, to our going down to the house at once? There may possibly be some small point which might be suggestive.”

“I was going to propose it, Mr. Holmes; but I thought it well to put you in touch with all the facts before we go. I suppose if anything should strike you—” White Mason looked doubtfully at the amateur.

“I have worked with Mr. Holmes before,” said Inspector MacDonald. “He plays the game.”